A porous organic polymer, a preparation method and application thereof

Abstract

The application relates to an organic porous polymer and a preparation method and application thereof, and belongs to the field of porous material preparation. The preparation method is simple, low in cost, uses a triptycene six-substituted derivative as a reaction monomer, and through a Yamamoto reaction, self-polymerization is generated under the action of a catalyst to obtain the organic porous polymer. The porous polymer is more stable, resistant to high temperature, resistant to physical and chemical corrosion, can realize selective adsorption, separation and efficient storage of propyne gas at the same time.

Description

Technical Field

[0001] This invention relates to the field of porous material preparation, and more specifically, to a class of organic porous polymers, their preparation methods, and applications. Background Technology

[0002] Light-chain hydrocarbons, as major downstream products of petrochemicals and also as important industrial raw materials, are deeply integrated into all aspects of people's lives. In 2015, global propylene production reached 114 million tons, which was largely used to synthesize polypropylene, widely used in clothing, medical devices, pipelines, chemical containers, and food and pharmaceutical packaging. Propylene obtained through industrial cracking often contains trace amounts of propyne products, which can poison the catalyst during subsequent polymerization, thus affecting polypropylene synthesis. Currently, industrial methods mainly use cryogenic distillation or selective catalytic hydrogenation to remove trace amounts of propyne gas from propylene gas. However, the former often requires significant energy consumption and is complex, while the latter is challenging due to the similarity in properties between propyne and propylene gases, and easily generates byproducts such as propane. Adsorption separation technology has gained increasing recognition from researchers in recent years due to its green, low-carbon, and simple process.

[0003] Meanwhile, propyne gas, as an important industrial raw material, can be used to produce chemicals such as acetone and is widely used in the fine chemical industry. However, as a flammable gas, it often poses certain safety hazards during transportation and storage. In addition, the currently used high-pressure steel cylinders and other storage methods result in significant additional energy consumption. Utilizing porous materials for propyne adsorption and storage is a promising alternative solution to these problems. Patent specification CN111298772A discloses a metal-organic framework material for the adsorption and separation of propyne and propylene. This material utilizes metal ions, inorganic anions, and organic ligands to construct a relatively regular layered porous structure, enabling effective selective adsorption of propyne gas. Furthermore, patent specification CN112661971A discloses a thorium coordination polymer for propyne storage, which, with its excellent pore structure, can achieve efficient adsorption and storage of propyne under mild conditions. CN104371112A discloses an organic porous polymer and its adsorption application in hydrogen. However, the monomer structure used in this polymer is too complex, resulting in high cost and an overly cumbersome preparation method. Furthermore, there are no significant research results regarding its adsorption in the propylene / propyne system. In summary, the aforementioned porous materials or their preparation methods have many problems, and in terms of application, the adsorption and storage capacity for propyne needs further improvement. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a porous organic polymer for the adsorption and separation of propylene and propyne, exhibiting good propyne storage performance, its preparation method, and its applications. The porous organic polymer material prepared by this invention, based on its excellent pore structure, can effectively and selectively adsorb propyne gas with high capacity, and can be applied to the storage and transportation of propyne.

[0005] According to one embodiment of the present invention, the present invention first provides an organic porous polymer based on triptene, characterized in that the organic porous polymer comprises repeating units and aromatic linking units connected to the repeating units, wherein the repeating units are hexasubstituted triptene derivatives of the following formula (1):

[0006]

[0007] The aromatic connecting unit is as follows (2):

[0008]

[0009] In formula (2), n = 2 to 4; R1 and R2 are N or C, and R3, R4, R5 and R6 are each of the independent H, CH3, NH2, OH and COOH groups;

[0010] Furthermore, in the organic porous polymer, the repeating units and the aromatic connecting units are arranged such that any two repeating units are connected through the aromatic connecting units, and any two aromatic connecting units are connected through the repeating units. In equations (1) and (2), Both represent connection sites.

[0011] According to one embodiment of the present invention, the present invention also provides a method for preparing the above-mentioned organic porous polymer, the preparation method comprising:

[0012] S1: Using a triterpenoid hexasubstituted derivative with terminal halogen atoms as a reaction monomer, a self-polymerization reaction is carried out through the Yamamoto reaction in the presence of a catalyst;

[0013] S2: Hydrochloric acid is added to the mixture obtained from the self-polymerization reaction to obtain a white flocculent precipitate, which is then separated from the liquid phase by vacuum filtration;

[0014] S3: Wash the precipitate and vacuum dry it to obtain the porous organic polymer.

[0015] According to one embodiment of the present invention, the catalyst is a metal-organic catalyst, preferably an organocopper or organonitrogen catalyst.

[0016] Preferably, the organonitrile catalyst uses bis(1,5-cyclooctadiene)nickel as the catalyst.

[0017] According to one embodiment of the present invention, the reaction temperature of the self-polymerization reaction in step S1 is 80-110°C, and the reaction time is 18-168 hours.

[0018] According to another embodiment of the present invention, the present invention also provides an application of the porous organic polymer prepared by the above preparation method in the adsorption and separation of propylene and propyne gases.

[0019] The above application involves using a porous tripterene polymer as a packing material in a fixed bed for the adsorption and separation of propyne impurities in propylene gas. The propyne content in the mixed gas is 0.1%–50%, the separation temperature is 25°C, the separation pressure is 1 atm, and the mixed gas flow rate is 0.5–1.5 mL / min. -1 .

[0020] For the adsorption and storage of propyne gas, the preferred adsorption temperature is -25 to 30°C, and the adsorption pressure is 0.5 to 5 atm. The lower the temperature and the higher the pressure, the greater the amount of propyne gas adsorbed by the material.

[0021] Preferably, the propyne gas separation process involves desorbing and releasing the stored propyne gas under conditions of increasing temperature from -25°C to 50°C and decreasing pressure from 5 atm, thereby enabling the reuse of porous organic polymer materials.

[0022] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages:

[0023] 1. The obtained organic porous polymer can simultaneously achieve selective adsorption and separation of propyne gas as well as efficient storage of propyne gas. Its dynamic separation selectivity for a mixture of propylene and propyne gas can reach 3.44, and its propyne gas storage capacity at 253K can reach 1182 cm³. 3 g -1 .

[0024] 2. The resulting organic porous polymer is more stable, resistant to high temperatures, and resistant to physical and chemical corrosion. Attached Figure Description

[0025] Figure 1 The breakthrough curve of the 999 / 1 (v / v) propylene-propyne mixture in Example 1 on PTN-1;

[0026] Figure 2 The diagram shows the propyne adsorption of the triterpenoid porous organic polymer PTN-1 in Example 1 at 253 K. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0028] Example 1

[0029] 0.4 g of the hexasubstituted triptene (1,2-triptene-hexachlorobenzene) shown in formula (3) was mixed with 0.5 g of 2,2'-bipyridine, 1 g of bis(1,5-cyclooctadiene) nickel, and 0.4 mL of 1,5-cyclooctadiene in 40 mL of dimethylformamide under a nitrogen atmosphere and heated and stirred at 85 °C for 18 hours. Adding hydrochloric acid to the resulting mixture yielded a white flocculent precipitate, which was separated from the liquid phase by vacuum filtration. The precipitate was washed sequentially with ultrapure water, ethanol, tetrahydrofuran, acetone, and dichloromethane, and then dried under vacuum to obtain the target product PTN-1.

[0030]

[0031] Example 2

[0032] 0.3 g of the hexasubstituted triptene (1,2-triptene-hexachlorobiphenyl) shown in formula (4) was mixed with 0.5 g of 2,2'-bipyridine, 1 g of bis(1,5-cyclooctadiene) nickel, and 0.4 mL of 1,5-cyclooctadiene in 40 mL of dimethylformamide under a nitrogen atmosphere and heated and stirred at 85 °C for 18 hours. Adding hydrochloric acid to the resulting mixture yielded a white flocculent precipitate, which was separated from the liquid phase by vacuum filtration. The precipitate was washed sequentially with ultrapure water, ethanol, tetrahydrofuran, acetone, and dichloromethane, and then dried under vacuum to obtain the target product PTN-2.

[0033]

[0034] Application test case:

[0035] The products obtained in Examples 1-2 were packed into a fixed bed. After activating the adsorbent, a propylene / propyne mixture (999 / 1, v / v) was used as the gas source. The gas to be tested was passed through the fixed bed at 25°C and 1 atm, with a gas flow rate of 1.0 mL min⁻¹. The components of the permeate gas were detected by gas chromatography equipped with an FID detector. Figure 1 The breakthrough curve is shown. After a single measurement, the fixed bed was cleaned and regenerated using a 10 mL min⁻¹ helium flow at 90 °C. After regeneration five times, the adsorption capacity of Examples 1-2 was measured again.

[0036] Table 1 Comparison of Product Performance in Examples 1-2

[0037]

[0038] Another 100 mg of the triterpenoid porous organic polymer obtained in Example 1 was tested for propyne adsorption performance using a gas adsorption instrument (Micromeritics ASAP2020) at 273 K. Figure 2 The gas adsorption curve is shown.

[0039] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A porosilicate-based organic polymer, characterized in that, The organic porous polymer comprises repeating units and aromatic linking units connected to the repeating units, wherein the repeating units are of the following formula (1): The aromatic connecting unit is as follows (2): In formula (2), n = 2 ~ 4; R1 and R2 are C, and R3, R4, R5 and R6 are each of the independent H, CH3, NH2, OH and COOH groups; Furthermore, in the organic porous polymer, the repeating units and the aromatic connecting units are arranged such that any two repeating units are connected through the aromatic connecting units, and any two aromatic connecting units are connected through the repeating units. In equations (1) and (2), " "All of these indicate connection sites." 2. A method for preparing the organic porous polymer as described in claim 1, characterized in that, The preparation method includes the following steps: S1: Using a triterpenoid hexasubstituted derivative with halogen atoms at the end as a reaction monomer, a self-polymerization reaction is carried out through the Yamamoto reaction in the presence of a catalyst; S2: Hydrochloric acid is added to the mixture obtained from the self-polymerization reaction to obtain a white flocculent precipitate, which is then separated from the liquid phase by vacuum filtration; S3: Wash the precipitate and vacuum dry it to obtain the organic porous polymer.

3. The preparation method according to claim 2, characterized in that, The catalyst is a metal-organic catalyst, which is an organocopper or organonickel catalyst.

4. The preparation method according to claim 3, characterized in that, The organonitrile catalyst uses bis(1,5-cyclooctadiene) nickel as the catalyst.

5. The preparation method according to claim 2, characterized in that, The reaction temperature for the self-polymerization reaction in step S1 is 80-110 °C, and the reaction time is 18-168 hours.

6. The application of the organic porous polymer as described in claim 1 in the separation of propylene and propyne gases.

7. The application according to claim 6, characterized in that, The separation process of the propyne gas involves desorbing and releasing the stored propyne gas under conditions where the temperature increases from -25°C to 50°C and the pressure decreases from 5 to 0 atm, so as to achieve the reuse of the organic porous polymer.

Images